The present measuring tools including a protractor, a ruler, and a right-angle gauge are independent protractor, ruler, and right-angle gauge for indicating an angle of 30°, 45°, 60°, and 90°, but these measuring tools do not provide other angles for quick drawings. If it is necessary to draw an angle other than those mentioned above, a protractor is needed. However, a general protractor includes a starting edge at the internal side of a straight edge and a center point disposed thereon. In the measurement of an angle, a small gap is produced between the straight edge and the starting edge, and thus users or students may take the straight line as a base and the center as the center point by mistake for the drawing. As a result, there is an error of the measured angle which is measured by using the center of the starting edge. In the present procedure of drawing an angle or a straight line of a specific length, it is necessary to draw the lines separately and then connect the lines to form an included angle or a figure with a different angle. As to the present measuring tools sold in the market, users have to use a combination of these measuring tools to draw the required angle or straight line of a specific length. If a student forgets to bring one of the measuring tools, the student may not be able to complete the drawing. These measuring tools usually provide a single function such as a protractor, a ruler, a triangle or a right-angle gauge, and thus the users can only draw an incomplete figure by one of these measuring tools. In the process of drawing a figure by using these measuring tools, a user may use any length in any direction or with a specific angle, but the user must carry the common protractor, ruler, triangle, or right-angle gauge to complete the required figure, and thus causing inconvenience for drawing figures by these measuring tools.